Field
The present invention relates to a valve operating device for an internal combustion engine including an engine valve that is used as an intake valve or an exhaust valve.
Discussion of Background
There has been known an engine valve in which a part of an outer face of a valve stem is formed as a small diameter area (refer to a following Patent Literature 1, for example).
Specifically, in the engine valve disclosed in Patent Literature 1, a part of the outer face of the valve stem that slides along the stem guide is formed as a small diameter area, and thereby the engine valve is reduced in weight.
Following is a list of patent literatures which the applicant has noticed as related arts of the present invention.
Patent Literature 1: Japanese Patent Application Publication No. 62-186007 A